The light is controlled by the relay. It can signal two things. Normally it comes on and then extinguishes after the relay thinks the pre-glow plugs have gotten hot enough (the relay maintains power to the plugs until it reaches the safety time-out). The relay also use the light to signal the operator when the system requires service, which is what it is telling you now by not coming on when the relay energizes the plugs.
You could measure the resistance of the plugs (normally 0.7 ohms) or measure current flow to the plugs to test them, or just replace them all and see if that clears the problem. Work! If you have money to burn, replace the relay, but that is the second least likely component to fail (the least likely failure is the dash light). -- Max Dillon Charleston SC '87 300TD '95 E300 _______________________________________ http://www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
